Seven ingredients, which gave it a second name: nanairo-jiru, seven-color soup. Soybeans, burdock, eggplant, carrot, kabocha, fried tofu, juroku-sasage beans. Whatever the summer has produced that week, all of it in a miso broth.

The constraint is religious and specific. In Zen households, taking life during the Obon period is forbidden. So no meat and no fish, and, less obviously, no bonito flakes and no dried sardines either. The stock has to come out of the vegetables themselves and nothing else. What arrives is a crowded, generous bowl with nothing animal anywhere in it.

There is a written trace of it, and it is older than you might expect. The Matsusaka Fuzokuki, a record of local customs and observances compiled in 1813, describes a soup with burdock, eggplant, kanpyo, and soybeans put in together in quantity, which appears to be this.

It is made across the Chunansei and Higashi-Kishu areas of Mie during Obon, and it is now served in Matsusaka school lunches. A dish whose entire shape was decided by a prohibition, cooked once a year for the dead who are visiting, has ended up on a tray in front of a nine-year-old on an ordinary Tuesday in August.